Manuals and technical information
What is the Super Cylinder?
An unvented hot-water cylinder designed by Heat Geek and made by Newark Cylinders. Larger coils help a heat pump transfer heat at a lower flow temperature. They do not make the cupboard any bigger.
It stores domestic hot water, with heating-system water passing through the coils. Older documents call it the HG Series. The current range has 14 models, with 4 m² or 6 m² total coil area.
Model codes explained
Each part of the code:
- HG: the Heat Geek cylinder range.
- 200: nominal 200-litre size class. The actual stored-water volume is listed separately.
- A: the main range. Newark recommends these taller shapes where they fit.
- B: an alternative, shorter shape for restricted height.
- 4: 4 m² total coil area, made up of two 2 m² coils.
- 6: 6 m² total coil area, made up of two 3 m² coils.
HG200A4 and HG200A6 are both 1960 mm high × 475 mm diameter. The larger coils in the A6 leave 181 L of stored water, compared with 187 L in the A4.
A-model sizes and dimensions
Overall dimensions include the standard insulation and casing. Water volume excludes the space occupied by the coils. Source: v4.1 manual, pages 8–10.
| Model | Height | Diameter | Stored water | Total coil area |
|---|---|---|---|---|
| HG150A4 | 1540 mm | 475 mm | 137 L | 4 m² |
| HG200A4 | 1960 mm | 475 mm | 187 L | 4 m² |
| HG200A6 | 1960 mm | 475 mm | 181 L | 6 m² |
| HG250A4 | 1710 mm | 550 mm | 237 L | 4 m² |
| HG250A6 | 1710 mm | 550 mm | 231 L | 6 m² |
| HG300A6 | 2045 mm | 600 mm | 281 L | 6 m² |
| HG350A6 | 1935 mm | 650 mm | 331 L | 6 m² |
| HG400A6 | 1625 mm | 750 mm | 381 L | 6 m² |
| HG450A6 | 1805 mm | 750 mm | 431 L | 6 m² |
| HG500A6 | 1985 mm | 750 mm | 481 L | 6 m² |
View the original A-model dimensions and specifications
B-model sizes for restricted height
The B models trade height for width. The same allowance for pipework, valves and access still applies. Source: v4.1 manual, page 11.
| Model | Height | Diameter | Stored water | Total coil area |
|---|---|---|---|---|
| HG200B4 | 1420 mm | 550 mm | 187 L | 4 m² |
| HG230B6 | 1610 mm | 550 mm | 211 L | 6 m² |
| HG250B4 | 1450 mm | 600 mm | 237 L | 4 m² |
| HG300B6 | 1735 mm | 650 mm | 281 L | 6 m² |
View the original B-model dimensions and specifications
Before ordering: check the delivery route, supported full weight, service access and safety discharge route. Extra insulation or bespoke connections can change the space required. A cylinder fitting through the door is a useful start.
Connections and fitting
| Connection or component | v4.1 specification |
|---|---|
| Coil flow and return | Four 28 mm pipe stubs, two per coil |
| Cold inlet | 1-inch female BSP, with 35 mm internal diffuser |
| Hot outlet | 1-inch female BSP |
| Temperature sensors | Two 10 mm dry pockets in ½-inch female BSP connections |
| Secondary return | 22 mm compression |
| Temperature and pressure relief connection | ¾-inch female BSP |
| Drain connection | ½-inch female BSP |
| Backup immersion | 3 kW; 1¾-inch female BSP boss |
| Cylinder working pressure | 3 bar normal; 6 bar maximum |
Version check: v4.0 introduced the four separate coil ports. v4.1 changed them to 28 mm pipe stubs and altered some connection positions. Use the drawing for the supplied version when planning pipework.
The coils can be used separately or combined externally. The manual shows a reverse-return parallel arrangement for combining them and explains how to purge each coil individually.
View the connections and twin-coil arrangement
This is an unvented cylinder. Allow for its expansion vessel, inlet group, temperature/pressure protection and discharge pipework. The Mini Store's different arrangement does not carry over to this cylinder. Follow the complete installation manual and arrange annual unvented-cylinder servicing.
What matters for hot-water performance?
Coil size, water demand and controls need to work together. A larger coil can transfer heat with a smaller temperature difference. The cold-inlet diffuser helps preserve hotter water above cooler water, known as stratification. Heat Geek explains the design here.
I would size the cylinder around measured shower flow, baths and the busiest sequence of use. More storage can let you run at a lower temperature while still meeting that demand. Coil area alone does not guarantee a recovery time or heat-pump efficiency.
Super Cylinder or Mini Store?
| Product | Water stored in the shell | Water passing through the coil |
|---|---|---|
| Super Cylinder | Domestic hot water | Heating-system water |
| Mini Store | Heating-system water | Mains water supplying the taps |
Their litre figures describe different things. I like the Mini Store where space is tight; our Mini Store guide includes installation photos and customer feedback on showers and baths.
Frequently asked questions
Does it include an immersion heater?
Yes. The v4.1 component list includes a 3 kW immersion for backup or boost. Confirm how it will be wired and controlled as part of the installation.
What guarantee does Newark provide?
The manual states five years against manufacturing defects, extended to seven for qualifying Heat Geek installations registered with Newark. Annual service records are required, and exclusions include corrosion. Read the full conditions on page 4.
Can it be used with artificially softened water?
Newark says artificially softened mains water is generally suitable. The v4.1 manual recommends maintaining salt-based softeners correctly, states a maximum chloride concentration of 200 mg/L and recommends calcium carbonate of 100–200 mg/L. That recommended range leaves some hardness in the water. Newark excludes corrosion from its manufacturer’s guarantee. See the water-quality guidance on page 14.
Can it be used with a private water supply?
Newark's buyer conditions specify UK public-mains water and exclude private sources such as wells and boreholes. Check this before choosing one for a rural property.
Check the model before ordering
For a Lincolnshire installation, send Vector Heat the model code, cupboard dimensions and hot-water requirements.